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Síntesis eficiente de anílidos atropisoméricos ópticamente activos a través de una reacción catalítica asimétrica de
Osamu Kitagawa1, Masashi Takahashi, Masatoshi Yoshikawa
1Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
Journal of the American Chemical Society
|March 18, 2005
Resumen
Este estudio demuestra un nuevo método catalítico asimétrico de N-arilación utilizando un catalizador de acetato de paladio. El proceso crea eficientemente anílidos atropisoméricos ópticamente activos y lactamas con alta enantioselectividad.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Catalización asimétrica por catálisis asimétrica.
- Química Medicinal La Química Medicinal es un campo de estudio de la química medicinal.
Sus antecedentes:
- La N-arilación es una reacción crucial en la síntesis orgánica.
- El desarrollo de métodos enantioselectivos para la N-arilación es importante para la creación de moléculas quirales.
- Los compuestos atropisoméricos con ejes quirales N-C son valiosos en productos farmacéuticos.
Objetivo del estudio:
- Desarrollar una N-arilación asimétrica y catalítica de los orto-tert-butilo-NH-anilidos.
- Para sintetizar anílidos atropisoméricos ópticamente activos y lactamas.
- Para lograr una alta enantioselectividad en estas transformaciones.
Principales métodos:
- Utilizando el (R) -DTBM-SEGPHOS-Pd(OAc) 2 como catalizador.
- Reaccionando los orto-tert-butilo-NH-anilidos con el 4-nitroiodobenzeno.
- Realiza reacciones de N-arilación tanto intermoleculares como intramoleculares.
Principales resultados:
- Se ha logrado una alta enantioselectividad (89-95% ee) en la N-arilación de anilides.
- Sintetizó con éxito anílidos atropisoméricos ópticamente activos con un eje quiral N-C.
- Lactamas atropisoméricos obtenidos con alta pureza óptica (94-96% ee) a través de la N-arilación intramolecular.
Conclusiones:
- El sistema catalítico desarrollado es eficaz para la N-arilación asimétrica.
- Este método proporciona acceso a valiosos compuestos atropisoméricos quirales.
- El enfoque es adecuado para la síntesis intermolecular e intramolecular de moléculas complejas.
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